Vertigo modesta (Cross Vertigo)

Classification Level

Description

Domain: Eukarya

Members of this domain have a true nucleus as well as membrane bound organelles.

Kingdom: Animalia

Animals are classified by their lack of a cell wall, and that they are multicellular and heterotrophic.

Phylum: Mollusca

Molluscus is Latin for “soft” and it is in this phylum to which soft-bodied snails and slugs belong (Martin, 2000).

Class Gastropoda

Gaster and podos are Greek for “belly” and “foot” respectfully.  Animals found in this class have a muscular foot, which is found on the animal’s ventral side and used for locomotion (Martin, 2000).

Subclass: Pulmonata

Pulmo is Latin for “lung” and these animals exchange gas with the use of a lung-like cavity (Martin, 2000).

Order: Stylommatophora

Stylos is Greek for “pillar.”  Members of this order have eyes found on the tip of the taller pair of their two retractile tentacles (Martin, 2000).

Family: Pupillidae

This family is classified based on the arrangement of tiny lamellae (tooth-like structures) about the aperture of the shell (Martin, 2000).

Genus: Vertigo

Members of this genus are characterized by the four to six lamellae that protrude into the aperture; they also have a translucent brown shell that is oblong in shape (Pearce et al., 2004).

Species: Vertigo modesta

This species of snail has four lamella or teeth that protrude from the aperture of the snail.  The four teeth are arranged in a manner that two are directly across from another, creating a cross-like shape, hence the name Cross Vertigo.  Subspecies can then be characterized on the prominence and placement of a fifth lamella.  As an example in comparison to Vertigo modesta modesta, Vertigo modesta parietalis has a very distinct angular fifth lamella (Lee, 2007).